How many times has Doom possessed “the power cosmic”?
There have been several times when Doom has usurped the power of a cosmic being and absorbed in into himself. The first time was in Fantastic Four # 57, when he stole the power of the Silver Surfer. He was defeated only when he flew into the barrier that kept the Surfer trapped on Earth, allowing the Surfer to regain his power when Doom was repelled. In Secret Wars # 10, Doom absorbs some of the power of Galactus, and then the Beyonder, perhaps becoming more powerful than he has ever been at any other time. He used the technology of Galactus’ worldship to achieve that goal. However, Doom lost his grip on reality and was finally defeated by Captain America and the Beyonder. Finally, in Fantastic Four # 375, Doom absorbs the power of the rogue Watcher, Aron, which he uses to battle the Fantastic Four. Doom loses his power through a device that Reed creates to defeat him (lucky shot).